just

just is a handy way to save and run project-specific commands.

This readme is also available as a book. The book reflects the latest release, whereas the readme on GitHub reflects latest master.

(中文文档在 这里, 快看过来!)

Commands, called recipes, are stored in a file called justfile with syntax inspired by make:

You can then run them with just RECIPE:

$ just test-all
cc *.c -o main
./test --all
Yay, all your tests passed!

just has a ton of useful features, and many improvements over make:

• just is a command runner, not a build system, so it avoids much of make’s complexity and idiosyncrasies. No need for .PHONY recipes!

• Linux, macOS, Windows, and other reasonable unixes are supported with no additional dependencies. (Although if your system doesn’t have an sh, you’ll need to choose a different shell.)

• Errors are specific and informative, and syntax errors are reported along with their source context.

• Recipes can accept command line arguments, including flags and options.

• just has a rich expression language and many built-in-functions.

• Wherever possible, errors are resolved statically. Unknown recipes and circular dependencies are reported before anything runs.

• just loads .env files, making it easy to populate environment variables.

• Recipes can be listed from the command line.

• Command line completion scripts are available for most popular shells.

• Recipes can be written in arbitrary languages, like Python or Node.js.

• just can be invoked from any subdirectory, not just the directory that contains the justfile.

• justfiles can be organized into multiple files using modules and imports.

• And much more!

If you need help with just, please feel free to open an issue or ping me on Discord. Feature requests and bug reports are always welcome!